Spark-plttg



A. M. C. WILSON.

SPARK PLUG.

kAPPLlcATloN HLED Aus.14. 1919.

Patented Nov. 23, 1920.

WQ vs- 5.55:

Y. 4 .v A

UNITED. sTArss PATENT oFFica.-k

ARBA M. C. WILSON, OFy SALINE, MICHIGAN.

, SPARK-PLUG.

To all lwhom t may concern; Beit known that I, AREA M. C. WILSON, a citizen of the United States, residing at Saline, in the county of VVashtenaw and.v

State of Michigan, have invented certain new and useful Improvements in Spark- Plugs; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable lothers skilled in the art to which it appertains to make and use the same.

rIhe present invention relates to spark` plug is in working condition, without the` necessity of removing the plug or making tests. e

A further object is the provision of novel spark producing means, and means enabling the spark gap to be adiusted quickly and conveniently. i

A still further of sparks around the inner end portion of the plug, to assure of perfect ignition.

.The invention has for its object the pro-k vision of the nature indicated, comprisinga novel assemblage and construction yof they component elements, in order that the device will be thoroughly,practicaheiiicient and reliableV in use, as well as being comparatively simule and inexpensive in'construction.

With the foregoig and other objects in view, which will be apparent as the description proceeds, the invention resides in the construction and arrangement of parts hereinafter descsibed and claimed, it being understood that changes can be madewithout departing rroi i the spirit of the invention.

The invention is illustrated in the accompanvinv drawinmwherein lFigure 1 is an elevation of the improved ug. P Fig. 2 is a longitudinal section thereof.

In carrying out the invention, there is provided a metallic plug member 1, kwhich is screw threaded to screw into the engine cylinder, as usual, and which is also formed for the engagement of a wrench in applying and removing the plug. The member 1 is Specification of Lettersilatent. Patented NOV, Application Jfiled August 14,1919.` serial No. 31.7551.

obiect is toprov'ide a seriesv provided at its outer end with a screw threaded counter-bore 2 into which is threaded the inner end of a tubular metallic sleeve or shell 3. An insulator ycore 4 of porcelain or other suitable insulating material extends through the bore of the member 1, and projects partially into the shell 3 and partially from the inner end of the member l.v This insulator 4 is provided near its inner end With an annular groove 5, and

has an enlargement 6 at its inner end. A bushing?v 1s iitted on the neck or reduced y portion of the insulator 4 within the groove 5, and is screw threaded into the inner end of the member l, to retain the insulator in place. The insulator can be divided for the purpose ofgetting the bushing there-on, or'the parts can'be assembled in any other practical Way.

` conductingrod 8 extends longitudinally through/the kinsulator 4, and is provided at its innerend with a head 9, and at its outer end with an electrodeterminal 10, and a nut 11is screw threaded onto the outer end p0rtion of the rod 8 and bears against the outer end'of the insulator 4, to firmly clamp said i rod within the insulator. This rod serves to conduct the electrical energy'through said f insulator. v, n

In order to provide multi-spark gap, a metallic .washer orring 12i`s clamped within the groove 5 between the -bushing 7 and enlargement 6, anda similar washer or ring 13 isclamped betweenthe head 9 and enlargement 6.` yThese kwashers are provided at their outer edgeswithannular flanges 14 extending toward onel another around enlargement 6, andtheedges'of said flanges lare toothed or serrated, with the teeth or points alternating, so as to provide a continuous annular zig-zag spark gap around the inner portion of the plug. This will Vprovide `forthe production of a large number of sparks around the plug, to assure of perfect ignition, andthe circumference of the enlargement 6 has an annular groove 15 gap and electrode points, The washer 12 is clamped in place between the enlargement 6 and bushing 7, and -in contacting with said bushing Will be in electrical connection with plug numberel, so as to be grounded to the engine whereas the washer 13 is held in place by the head, 9 and will thus be in electrical connection with rod 8. By loosening therod 8, the washer 13 yis extending around the Linner side of the spark By Vseparating the washers 12 and 13, theVY spark gap is also increased. When the plug member 1 is screwed into the cylinder, the

sparking or electrode washers 12 and 13 Will extend into the chamber of the cylinder, to effectively ignite the charge, and the inner end oi" the plug is not chambered as Vusual, so as to avoid the accumulation of carbon as occurs in such a chamber.

A second insulator or core 16 is screw threaded into theV outer end ot the tubular shell 3, being retained in its adjusted position by means of a. lock nut 17 screwed on said insulator and bearing against said end of the shell. The inner end portion of the insulator 16 which extends within theV shell, is reduced, as atv 1S, and nts within a glass or other transparent insulating tube 19, that serves as a lining for the shell 3. rThis tube 19 is fitted within the shell and extends into the member 1 around insulator l, so that said tube has its end portions fitted on the adjacent ends of the two insulators, to, inclose the spark gap between the insulators. The shell 3 has an opening or window 20 across which tube 19 extends, and permitting observation of the intensifying spark gap. A conductor rod 21 in alinement with the rod 8 extends longitudinally through the insulatorV 16, and is provided at its' inner end with conical head22 seating against the inner end of the insulator 16, and providing an electrode terminal adjacent to the terminal 10 to provide an intensifyingv spark gap. A binding nut 23 is threaded on the outer protruding terminal of the rod21 Jor clamping the conductor wire to complete the electrical circuit.

By the provision ofthe spark lgap between the rods 8 and 21,' this will Vserve to intensify the current and'sparks produced between the ignition electrodes at the inner end of the plug, and furthermore, by looking through the opening 20, an indication can be had of whether or not the plugis in Vworking condition.- l/Vhen the plug is in working condition the sparks between the electrode terminalsl() and 22 will indicate this fact, whereas it' such sparks `are absent, or are of improper character, it'wi'll be known that the plug is out'of commission. The gap between the terminals y10 and 20 canV be adjusted to suit conditions, by loosening Ythe lock nut'17, and turning the insulator 16 accordingly, after which the lock nut is again tightened, to hold the parts in adjustment. l

Having thus described the what is claimed as new is 1. A spark plug comprising a vplug member, a tubular shell removably secured therein and extending therefrom, an insulator within said member extending into the shell, a second insulator having a screw threaded connection with the shell and entering same, a conducting rod extending through each insulator, the adjacent ends of said rods having electrode terminals providing an intensii'ying spark gap, a transparent tube litted within Ithe shell and on the adjacent ends of said insulators, the shell having an opening exposing the spark gap, and sparking electrodes between said member and rod of the first named insulator.

2. A'spark plug comprising a plug member, an insulator therein having an enlargement, a bushing iitted on said insulator and removably secured within said plug member, a conducting rod extending through said insulator, an electrode washer between said enlargement and bushing, a second electrode washer between said enlargement and rod opposite to the aforesaid washer, said washers having cooperating sparking points around said enlargement, and means for clamping said rod to the insulator.

3. A spark plug comprising a plug member, an insulator therein having anvannular groove, a bushing in said groove engaged with said member, said insulator having an enlargement, a conducting rod extending throught-he insulator, means on said'rod for clamping itin vthe insulator, an electrede washer between said enlargement and bushing, a second electrode washer between said enlargement'androd opposite to the aforesaid washer, said flanges p extending toward-` one anotherl around said enlargement and' provided'with sparking points.y Y

1n testimony whereof' I'h'ave signed' my naine tol this specification| in-'th'e 'presence *of two subscribing witnessesj ABBA Witsen' invention,

lVitnes'ses:

F. D JOHN GORDON.'

washers having 

